In daily life, people often selectively use fragrance substances or deodorant to generate sweet smell indoor, in order to eliminate stress and fatigue or to eliminate unpleasant smell in toilets and other places. Traditional fragrance diffusers generally realize diffusion of fragrance substances or deodorant by means of heat, wind or ultrasonic atomization. But, they have the following drawbacks. For example, heat sources of diffusers such as scented candles, tea lights, etc., are dangerous due to their open flames. Most wind diffusers are of open-typed, and it is difficult to control the volatilization degree of essential oil in such kind of diffusers. Atomization diffusers need water, and should be cleaned frequently. The above open-typed fragrance diffusers are subject to oil leakage and are not easy to be stored, and cannot control the degree of volatilization and mixing ratio of fragrant smells. Most of the existing closed fragrance diffusers require complicated control methods and complex devices to adjust fragrant smell concentration and mixing ratio, and therefore are expensive and are difficult to operate.